By the U.S. account, the force's agent -- 56-year-old Manssor Arbabsiar, an Iranian-born naturalized citizen living in Corpus Christi, Texas -- turned to a woman he met while working as a used car dealer to find a Mexican drug dealer-assassin, and he wound up with an informant instead, the Associated Press reported.

U.S. officials said they believe the sloppiness executing the assassination plot was due to inexperience with covert operations inside the United States and Mexico. The officials, speaking on condition of anonymity to discuss classified analysis, believe Iran hoped to disguise the assassination attempt as an al-Qaida attack.

The informant, a DEA agent, discussed with Arbabsiar the bombing of a D.C. restaurant frequented by al-Jubeir, according to the indictment.

Arbabsiar was arrested Sept. 29 during a layover at JFK International Airport in New York. He has since confessed, authorities said.